A detonation wave ignited in a geometrically unconfined homogeneous reactive gas mixture usually spreads in all directions from the ignition point. For a confined system, the detonation propagation may be affected by the confinement geometry, which can, in some cases, lead to detonation failure. According to S. S. Grossek, “Deflagration and Detonation flame Arresters”, American Institute of Chemical Engineers, New York, 2002, geometries that cause detonation failure are often used in detonation arresters to prevent the detonation from propagating through industrial pipelines. Detonation arresters are usually designed to stop both detonations and deflagrations, and the resulting geometries are often complex and create significant flow restrictions. If focusing only on quenching detonations, there are a few relatively simple ways to decouple the flame from the shock without putting obstructions in the flow.
One way to prevent a detonation from propagating through a channel is to line the channel walls with a porous material that damps transverse waves (see: G. Dupre, O. Peraldi, J. H. S. Lee, R. Knystautas, “Propagation of detonation waves in an acoustic absorbing walled tube” Prog. Astronaut. Aeronaut. 114 (1988) 248-263; also see A. Teodorczyk, J. H. S. Lee, “Detonation attenuation by foams and wire meshes lining the walls”. Shock Waves 4 (1995) 225-236; and also see M. I. Radulescu, and J. H. S. Lee, “The Failure Mechanism of Gaseous Detonations: Experiments in Porous Wall Tubes”. Combust. Flame 131 (2002) 29-46). Damping transverse waves weakens and destroys triple-shock configurations that are largely responsible for the energy release in a gaseous detonation wave, and the detonation eventually fails.
Another way to quench a detonation by decoupling the flame from the shock without putting obstructions in the flow is to use detonation diffraction phenomena (which is an interaction of a detonation wave with a divergent geometry) that may quench a detonation propagating from a smaller to a larger channel. Inserting a cylindrical expansion section of a larger diameter into a pipeline may stop a detonation if the pipeline diameter is small enough. Detonation diffraction is discussed in detail in the following references: (Y. B. Zeldovich, S. M. Kogarko, & N. N. Simonov, “An experiment investigation of spherical detonation in gases”, Soy. Phys. Tech. Phys. 1(1956) 1689-1713; S. M. Kogarko, “On the possibility of detonation of gaseous mixtures in conical tubes”, Izvestia Akad. Nauk SSSR, OKhN, 4(1956) 419-426; V. V. Mitrofanov, R. I. Soloukhin, “The diffraction of multifront detonation waves”. Sov. Phys. Dokl. 9(1965) 1055-1058; D. H. Edwards, G. O. Thomas, M. A. Nettleton, “The diffraction of a planar detonation wave at an abrupt area change”. J. Fluid Mech. 95(1979) 79-96; H. Matsui, J. H. S. Lee, “On the Measure of the Relative Detonation Hazards of Gaseous fuel-Oxygen and Air Mixtures”. Proc. Combust. Inst. 17(1979) 1269-1280; R. Knystautas, J. H. S. Lee, C. M. Guirao, “The critical tube diameter for detonation failure in hydrocarbonair mixtures”. Combust. Flame 48(1982) 63-83; S. A. Gubin, S. M. Kogarko, V. N. Mikhalkin, “Experimental studies into gaseous detonations in conical tubes”. Combust. Expl. Shock Waves 18(1982) 592-597; G. O. Thomas, D. H. Edwards, J. H. S. Lee, R. Knystautus, I. O. Moen, “Detonation diffraction by divergent channels”. Prog. Astranaut. Aeronaut. 106(1986) 144-154; F. Bartlma, K. Schroder, “The Diffraction of a Plane Detonation Wave at a Convex Corner”. Combust. Flame 66(1986) 237-248; D. A. Jones, M. Sichel, E. S. Oran, “Reignition of Detonations by Reflected Shocks”. Shock Waves 5(1995) 47-57; D. A. Jones, G. Kemister, E. S. Oran, M. Sichel, “The Influence of Cellular Structure on Detonation Transmission”. Shock Waves 6(1996) 119-130; D. A. Jones, G. Kemister, N. A. Tonello, E. S. Oran, M. Sichel, “Numerical Simulation of Detonation Reignition in H2—O2 Mixtures in Area Expansion”. Shock Waves 10(2000) 33-41; G. O. Thomas, R. Ll. Williams, “Detonation interaction with wedges and bends”. Shock Waves 11(2002) 481-492; B. Khasainov, H.-N. Presles, D. Desbordes, P. Demontis, P. Vidal, “Detonation diffraction from circular tubes to cones”. Shock Waves 14(2005) 187-192; J. H. S. Lee, “The Detonation Phenomenon”, Cambridge Univ. Press, (Cambridge, 2008); and F. Pintgen, J. E. Shepherd, “Detonation diffraction in gases”. Combust. And Flame 156(2009) 665-677).
According to the following publications (V. V. Mitrofanov, R. I. Soloukhin, “The diffraction of multifront detonation waves”. Soy. Phys. Dokl. 9(1965) 1055-1058; D. H. Edwards, G. O. Thomas, M. A. Nettleton, “The diffraction of a planar detonation wave at an abrupt area change”. J. Fluid Mech. 95(1979) 79-96; and R. Knystautas, J. H. S. Lee, C. M. Guirao, “The critical tube diameter for detonation failure in hydrocarbonair mixtures”. Combust. Flame 48(1982) 63-83): Experiments show that the detonation exiting from a tube to a large volume fails when the tube diameter is smaller than approximately 13 detonation cells. For a limited expansion section, however, the detonation can reignite when shocks produced by the failed detonation reflect from walls. These shock reflections may ether ignite a new detonation directly or promote a deflagration-to-detonation transition (DDT) in the expansion section. The probability of DDT may even increase for a larger expansion section, thus making this simple geometry unreliable for detonation quenching.
Therefore, the need exists for a method of preventing a detonation from propagating through a channel without creating flow restrictions in the channel. Further, the need exists for a geometry that would provide a more reliable detonation quenching.